1. Field of the Disclosure
The present disclosure relates to a panel acting as an active retarder, and more particularly, to a panel using polymer-dispersion-type liquid crystals, a method of fabricating the panel, and a 3-dimensional stereoscopic image displayable system including a panel acting as an active retarder.
2. Discussion of the Related Art
In general, a liquid crystal display (LCD) device may include two opposite electrodes and an LC layer formed therebetween. LC molecules of the LC layer may be driven due to an electrical field generated by applying a voltage to two electrodes. The LC molecules may have polarization characteristics and optical anisotropy. The polarization characteristics refer to changing an arranged direction of LC molecules according to an electrical field due to crowding of charges into both sides of the LC molecules when the LC molecules are placed in the electrical field. Optical isotropy refers to varying a path or polarization state of emission light according to an incident direction or polarization state of incident light due to fine, long structures of the LC molecules and the above-described arranged direction of the LC molecules.
Thus, the LC layer may exhibit a difference in transmittance due to voltages applied to two electrodes, vary the difference according to each pixel, and display 2-dimensional (2D) images.
Meanwhile, owing to the increased demand for LCDs capable of expressing further realistic stereoscopic images, LCDs capable of displaying 3D stereoscopic images have lately been developed.
In general, 3D stereoscopic images may be formed based on the principle of binocular stereoscopic vision. Thus, LCDs capable of displaying stereoscopic images using binocular disparity caused by two eyes spaced about 65 mm apart from each other, have been proposed.
Formation of 3D images will now be described in further detail. Left and right eyes, which may view an image of an LCD device, may respectively see different 2D images. When the two 2D images are transmitted through the retinae to the brain, the brain may precisely merge the two 2D images and reproduce the senses of depth and reality of an original 3D image. This phenomenon is typically referred to as stereoscopy.
To display 3D stereoscopic images, 2D image display devices, such as LCD devices, may adopt a stereoscopic image display technique using special glasses, a glasses-free stereoscopic image display technique, or a holographic display technique.
In addition, a stereoscopic image display device using polarized glasses and an active retarder serving as a shutter capable of converting left and right images into each other, has lately been suggested.
FIG. 1 is a cross-sectional view of a conventional stereoscopic image display device 1.
The conventional stereoscopic image display device 1 may broadly include an LC panel 10 including a first LC layer 22 and first and second polarizers 25 and 30, an active retarder panel 85, and polarized glasses 98.
In the case of the active retarder panel 85, first and second electrodes 53 and 73 may be disposed on inner side surfaces of two glass substrates 50 and 70 disposed opposite each other. Alignment layers 56 and 76 formed of a polymer, which may need a high-temperature process, may be formed on inner side surfaces of the first and second electrodes 53 and 73, respectively, and a second LC layer 80 may be formed between the alignment layers 56 and 76.
Accordingly, in the 3D image display device 1 including the active retarder panel 85 having the above-described construction, two glass substrates 15 and 20 may be used to form the LC panel 10, and two other glass substrates 50 and 70 may be required to fabricate the active retarder panel 85 including the alignment layers 56 and 76 that need a high-temperature process. Therefore, since the weight and volume of the 3D image display device 1 may increase, the conventional 3D image display device 1 may go against the recent trend toward lightweight, ultrathin display devices, preclude fabrication of large-area 3D image display devices, and comparatively increase fabrication costs.